Healing is from God. Products of the earth are for our use in healing.  If you are concerned about the meds themselves, pray over them as you would food.  I have used homeopathy for many years, along with modern medicines, minerals, vitamins, plants, etc.  The great saint Hildegard of Bingen used stones and gems, so I don't think anyone can say that when used with God in mind, prayerfully, that any form of medicine is inherently bad unless it is proven to do harm.  Practices like yoga are inherently bad because they are practices developed by men to worship idols.  Two different things entirely. I keep hearing of a movement to unsettle Catholics about the use of homeopathy, but I find their reasons anecdotal. Because they don't understand how it works and from the guy that supposedly invented it, they assume it's evil.  No one invented homeopathy.  They discovered it, uncovered it, which means, it was already there for our use for healing. I remain open to discovering specific ways homeopathy harms people in and of itself.  Until then, this is my opinion.      

If the practitioner used pagan language, spells, the sin is obvious. I think it depends on that.